Properly sizing your garage heater to your specific room size and type is an important step in optimizing comfort and reducing energy waste. A garage heater that is too large for the space will not heat the space more quickly.

A heater that is too large for the room will continue to heat for an extended period of time beyond the temperature set point, wasting energy. We call this a temperature swing. Alternatively, a heater that is too small will run for a longer period of time than would be necessary with a properly sized heater.

Use the below 4 easy steps to calculate the optimal garage heater size in watts per square foot.

Step 1. Select the heating zone your space is located in

Heating Zones

Step 2. Measure and calculate the square footage of your space by multiplying the Length x Width.

Step 3. Select the insulation values that best describes the insulation used in your space.

CoveHeater Application Insulation

Example: Heat Zone 2 / FHA Standard Insulation = 10W per Square Foot

Step 4. Multiply the total square feet by the watts per sqft based on the heating zone and your estimated insulation values to determine the correct wattage needed to heat your space.


Example: 750 Square Foot Room X 10W per Square Foot = Recommended Wattage: 7500W


Step 5. Purchase a Garage heater closest to the recommended wattage.